Back to EveryPatent.com
United States Patent |
5,325,658
|
Stahlecker
|
July 5, 1994
|
Spinning machine with false-twisting devices
Abstract
In the case of a spinning machine having several spinning stations, which
comprise drafting units, for the spinning of slivers fed in cans,
false-twisting elements are connected in front of the drafting units which
provide the slivers with a protective twist.
Inventors:
|
Stahlecker; Gerd (Eislingen/Fils, DE)
|
Assignee:
|
Stahlecker; Fritz (DE);
Stahlecker; Hans (DE)
|
Appl. No.:
|
871125 |
Filed:
|
April 20, 1992 |
Foreign Application Priority Data
Current U.S. Class: |
57/90; 57/328 |
Intern'l Class: |
D01H 013/04 |
Field of Search: |
57/90,315,341,343,328
|
References Cited
U.S. Patent Documents
2097540 | Nov., 1937 | Tracy | 57/328.
|
2256436 | Sep., 1941 | Kruse | 57/328.
|
2619790 | Dec., 1952 | Hardacre et al. | 57/343.
|
2710428 | Jun., 1955 | Nutter et al. | 57/315.
|
2936567 | May., 1960 | Russell et al. | 57/341.
|
3564829 | Feb., 1971 | Tsuzuki | 57/90.
|
3727391 | Apr., 1973 | Hiserman et al. | 57/315.
|
4700538 | Oct., 1987 | Varga et al. | 57/328.
|
Foreign Patent Documents |
0041484 | Dec., 1981 | EP.
| |
1785481 | Jun., 1971 | DE.
| |
1015780 | Jan., 1966 | GB.
| |
Primary Examiner: Hail, III; Joseph J.
Attorney, Agent or Firm: Evenson, McKeown, Edwards & Lenahan
Claims
What is claimed:
1. A ring spinning machine comprising:
a plurality of spinning stations which each contain a three-cylinder
drafting unit;
guiding devices which are between cans containing sliver and the drafting
units wherein slivers are in the range from 0.3 to 0.8 Nm, with one sliver
respectively being withdrawn from one of the cans and fed to the drafting
units by the guiding devices, the guiding devices forming at least one
deflecting guide for the slivers so that the slivers are withdrawn from
the cans in the upward direction and are then deflected downward to the
pertaining drafting units;
first mechanical false-twisting devices for each sliver arranged in the
area of the deflecting guide, said first false-twisting devices providing
the respective sliver with a false twist which at least partially runs
back to the can from which the sliver was withdrawn; and
second mechanical false-twisting devices for each sliver arranged directly
in front of the drafting units, said second false-twisting devices
providing a false twist to the respective sliver which runs back to the
deflecting guide,
wherein feeding rollers which are situated in front of the pertaining
false-twisting elements are connected in front of the drafting units and
the delivery speed of these feeding rollers is approximately 5 percent
lower than the feeding speed of the drafting units.
2. A spinning machine according to claim 1, wherein the guiding devices
each comprise a deflecting guide which divides the transport path of the
slivers into two essentially linear strand sections, and wherein the
false-twisting elements include a false-twisting element assigned to the
deflecting guide.
3. A spinning machine according to claim 1, wherein the first
false-twisting element is connected directly in front of the deflecting
guide.
4. A spinning machine according to claim 1, wherein the false-twisting
elements are connectable to driving means.
5. A spinning machine according to claim 1, wherein the false-twisting
element itself forms the deflecting guide.
6. A spinning machine according to claim 5, wherein the false-twisting
elements are drivable.
7. A spinning machine according to claim 1, wherein the false-twisting
elements are connectable to driving means.
8. A spinning machine according to claim 1, wherein the false-twisting
elements are connectable to driving means.
9. A spinning machine according to claim 1, wherein the guiding devices
include a deflecting guide for each spinning station which divides the
sliver transport path into two essentially linear strand sections.
10. A spinning machine according to claim 9, wherein the false-twisting
devices include a first false-twisting element disposed immediately
upstream of the pertaining deflecting guide.
11. A spinning machine according to claim 10, wherein the false-twisting
devices include a second false-twisting element disposed adjacent an
upstream end of a pertaining drafting unit.
12. A spinning machine comprising:
a plurality of spinning stations which each contain a three-cylinder
drafting unit;
guiding devices which are between cans containing sliver and the drafting
units wherein slivers are in the range from 0.3 to 0.8 Nm, with one sliver
respectively being withdrawn from one of the cans and fed to the drafting
units by the guiding devices, the guiding devices forming at least one
deflecting guide for the slivers so that the slivers are withdrawn from
the cans in the upward direction and are then deflected downward to the
pertaining drafting units;
first driveable false-twisting devices for each sliver arranged in the area
of the deflecting guide, said first false-twisting devices providing the
respective sliver with a false twist which at least partially runs back to
the can from which the sliver was withdrawn;
second driveable false-twisting devices for each sliver arranged directly
in front of the drafting units, said second false-twisting devices
providing a false twist to the respective sliver which runs back to the
deflecting guide; and
means for driving the first and second false-twisting devices, for
detecting a yarn break and for stopping the driving of the first and
second false-twisting devices in response to the detected interruption of
yarn production.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to a spinning machine having several spinning
stations for the spinning of slivers fed in cans into yarns, having
guiding devices for the guiding of the slivers from the cans to drafting
units pertaining to the spinning stations and having devices for
protecting the slivers on their transport path.
It is known (British Patent Document GB 1 015 780) to feed slivers to a
ring spinning machine in cans, withdraw them by way of rollers and then
guide them to pairs of transport belts which receive the slivers between
one another and transport them to the drafting units of the individual
spinning stations. Transport belts of this type require high expenditures.
In the case of a ring spinning machine with package feeding, it is known
(European Patent Document EP-0 041 484 B1) to guide the roving by way of a
stationary spiral which is to provide a false twist to the roving and thus
provide it with a higher strength.
Similar stationary false-twisting elements are also known in the case of
roving frames (German Patent Document DE-OS 1 785 481) in which slivers
are guided from cans to the drafting rollers.
In the older German Patent Application P 40 38 231.1, which is no prior
publication, it was suggested to provide the slivers during the withdrawal
from the cans with a true twist in that the cans are rotated about their
axes.
It is an object of the invention to feed also finer slivers from cans, of a
size range of from Nm 0.3 to 0.8, to a spinning machine, in which case
these slivers are sufficiently protected on their transport path and, if
possible, are no longer provided with a twist when entering into the
drafting units, and the expenditures for protecting the slivers are as low
as possible.
This object is achieved according to preferred embodiments of the invention
in that false-twisting elements are provided as the devices for the
protecting of the slivers which are connected directly in front of the
drafting units.
During their transport path, the slivers are provided with a sufficient
number of twists by means of the false-twisting elements so that they are
strengthened to such an extent that they are protected against faulty
drafts. Very long transport paths can be bridged in this manner. After
leaving the false-twisting elements, thus when entering the drafting units
pertaining to the spinning stations, the slivers will again be largely
untwisted because, as is known, the false twist opens up again behind the
false-twisting elements. However, the transport path between the
false-twisting elements and the drafting units is only short and withstood
by the slivers without suffering any damage. It is advantageous for the
fibers of the slivers to again be directed in parallel when entering into
the drafting units.
In a development of the invention, the guiding devices each have a
deflecting guide which divides the transport path of the slivers into two
essentially linear strands and to which a false-twisting element is also
assigned. Such a deflecting guide makes it possible, for example, to
deposit cans next to the spinning machine while leaving an operating aisle
and to guide the slivers, in the manner of a roof, over the aisle to the
spinning stations. The additional false-twisting element connected in
front of the deflecting guide provides a sufficient protective twist also
between the can and the deflecting guide because it cannot simply be
assumed that the false twist running back from the false-twisting elements
of the drafting units will propagate by way of the deflecting guides.
The false-twisting element assigned to the deflecting guide may be directly
connected in front of the deflecting guide. However, as an alternative, it
is also possible to design the false-twisting element itself as a
deflecting guide. In this case, the false twisting element provides the
sliver not only with the protective twist but is also used for the guiding
of the sliver.
Expediently, the false-twisting elements are drivable. It is therefore
possible to adapt the magnitude of the false twist to the respective fiber
material.
Advantageously, feeding rollers situated in front of the pertaining
false-twisting elements are connected in front of the drafting units, the
delivery speed of the feeding rollers preferably being 5% lower than the
feeding speed of the drafting unit. Thus, the circumstance is taken into
account that the slivers are shortened as a result of the false twist and
are lengthened again correspondingly behind the false twisting elements.
When feeding rollers are present, it is therefore necessary to coordinate
the speeds of the feeding rollers with the speeds of the feeding rollers
of the drafting unit with respect to one another. Such a coordination does
not present any problems technically but this aspect has to be taken into
account.
Other objects, advantages and novel features of the present invention will
become apparent from the following detailed description of the invention
when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial cross-sectional view of a machine system with a
spinning machine with spinning stations to which one sliver respectively
is fed by means of a can, a total of two false-twisting elements for
providing a protective twist being assigned to each sliver, constructed
according to a preferred embodiment of the invention;
FIG. 2 is an enlarged representation of a false-twisting element according
to FIG. 1;
FIG. 3 is a partial view similar to FIG. 1 with a deflecting guide assigned
to 'the slivers which, at the same time, is a false-twisting element,
constructed according to another preferred embodiment of the invention;
and
FIG. 4 is a view of a detail of FIG. 3 with a vertically adjustable holding
device for a false-twisting element.
DETAILED DESCRIPTION OF THE DRAWINGS
The spinning machine 1, which is shown only schematically in FIG. 1, is
provided on both sides of its longitudinal center plane M on each side of
the machine with a plurality of spinning stations 2 arranged next to one
another. Of the spinning stations, only one three-cylinder drafting unit
is illustrated.
In front of the spinning stations 2, an operating aisle 4 is situated for
operating personnel. On the side of the operating aisle 4 opposite the
spinning machine 1, cans 5 are deposited which, in a manner not shown in
detail, may be arranged in several rows. The cans 5 contain the fiber
material which is spun by the spinning stations 2.
The fiber material is fed to the spinning stations 2 as a sliver 6 produced
on a drafting frame. The slivers have a size of approximately Nm 0.3 to
0.8 so that they can be drafted to the desired yarn size by the
three-cylinder drafting units 3, in which case the respective pair of
feeding rollers 7 nevertheless rotates at a sufficient rotational speed so
that a concentricity is ensured.
The relatively fine slivers 6 are withdrawn from the cans 5 in the
direction of the arrow A by a feeding roller 8, are then transported in
the direction of the arrow B over the operating aisle 4 to another feeding
roller 9 which is used as a deflecting guide, and are then in the
direction of the arrow C essentially vertically fed to the pertaining
drafting unit 3 in front of which the sliver guide 10 is connected. The
slivers 6 drafted in the drafting units 3 are then fed in the direction of
the arrow D to a twisting element, such as a ring spindle, which is not
shown.
The cans 5 stand on conveyer belts 11 extending in the longitudinal
direction of the machine which are placed in a platform 13 arranged
slightly above the floor 12. The conveyor belts 11 are provided with
button-type take-along devices 14 which reach behind the inner lower edge
of the normally slightly elevated bottoms of the cans 5 and thus take them
along with a certain form closure, convey them and hold them in the
desired position. By means of the conveyor belts 11, which slide on the
platform 13 and the returning run 15 of which is guided back below the
platform 13, an automated supply and removal of the cans 5 can be
realized, in which case the cans 5, after a stoppage of the conveyer belts
11, automatically stop in the correct position in which they remain during
the spinning process.
On the relatively long transport path of the slivers 6, there is the danger
of faulty drafts which later cause size fluctuations in the produced
yarns. For this reason, it is provided to protect the slivers 6 during
their transport path against such faulty drafts.
In the area in front of the feeding roller 9, a false-twisting element 16
is situated. Another false-twisting element 17 is connected in front of
the respective drafting unit 3. This arrangement has the result that the
individual slivers 6 are in each case provided with a protective twist
between the feeding roller 8 and the false-twisting element 16 as well as
between the feeding roller 9 and the false-twisting element 17. In this
case, it may be provided to select the magnitude of the protective false
twist to be identical on both strand sections 18 and 19 of the slivers 6.
In this case, the slivers 6 are strengthened to such an extent that they
are protected against faulty drafts. In this manner, a very long transport
path can be bridged with the choice of the depositing of the cans 5 being
completely free, and the cans 5 may also be deposited as desired or
required on an elevated platform.
The false-twisting element 17, which is connected directly in front of the
drafting unit 3, is situated very close to the sliver guide 10 so that the
distance between the false-twisting element 17 and the pair of feeding
rollers 7, where the sliver 6 is essentially not protected by a false
twist, becomes as small as possible. Since the false twist produced by the
false-twisting element 17 does not necessarily reach beyond the feeding
roller 9, which to a certain extent acts as a twisting block, it is
provided that a second twisting element 16 is disposed directly in front
of the feeding roller 9. In this case also, the distance between the
false-twisting element 16 and the feeding roller 9 should be as short as
possible because the sliver 6 is largely untwisted in this area. Finally,
it is also useful to mount the feeding roller 8 very closely above the
upper opening of the can 5 because the sliver 6 is virtually not yet
protected by the false twist also between the can 5 and the feeding roller
8.
It is important that, before entering into the respective feeding roller
pair 7 of the drafting unit 3, the slivers 6 are virtually without any
twist. Therefore, despite the previously provided protective twist, the
fibers of the sliver 6 are again aligned in parallel and not, as in the
case of flyer rovings, spirally in parallel.
A false-twisting element 16 and 17 is illustrated in FIG. 2. This is a
simple tube 20 which has a crank-type deflection 21 and can be rotated in
a bearing 22. The bearing 22 is inserted in a holder 23 which can be
fastened on a longitudinal rail extending in the longitudinal direction of
the machine.
For the driving of the false-twisting element 16, 17, a narrow driving belt
24 which extends in the longitudinal direction of the spinning machine 1
is sufficient. A narrow toothed belt may also be used which is, for
example, 10 mm wide, and the tube 20 may be equipped with a small toothed
wheel. In the embodiment according to FIG. 2, the driving belt 24 acts
directly on the tube 20. So that contact pressure rollers are not
required, the driving belt 24 may extend in a slalom-type manner; that is,
in the case of one tube 20, it may rest against the top and in the case of
an adjacent tube 20, it may rest against the bottom.
It is quite safe for the false-twisting elements 16, 17 to extend from one
spinning station 2 to the next alternately around the left or the right.
Since the false twist opens up again before the slivers 6 enter into the
drafting units 3, it is not important whether the protective twist is a
right-hand twist or a left-hand twist. It has the same strengthening
protective effect in any case.
The false-twisting element 16, 17 shown in FIG. 2 is only an example. All
kinds of false-twisting elements may be used which are known from the
state of the art.
It is a basic idea that the sliver 6, which is too weak for the transport,
is strengthened by means of a false twist for a short time, thus during
the transport, in which case one or several false-twisting elements 16, 17
are used for each spinning station 2. In this case, the false-twisting
elements 16, 17 must each be mounted on the end of the strand sections 18,
19 to be protected. The introducing of the slivers may take place by using
suction air pistols. Care will be taken that the slivers 6 never travel
completely out of the cans 5, and an exchange of cans will also be carried
out sufficiently early so that a threading of the slivers 6 through the
false-twisting elements 16, 17 is an operation that occurs relatively
infrequently. As a result of the fact the false twist opens up in time in
front of the pair of feeding rollers 7, the sliver 6 retains its good
drafting capacity.
It may also be advantageous to assign stopping devices 50 to the
false-twisting elements 16, 17. These may, for example, be designed such
that a small sliding lever exists on each spinning station 2 which, as
required, lifts the driving belt 24 from the tube 20 of the false-twisting
element 16, 17. Since the tubes 20 rotate very slowly, a simple bearing
will be sufficient and may possibly even permit that the driving belt 24
for a short time drags over the rounded edge of a lifting lever. Such
stopping devices 50 may be electrically coupled with a yarn detector YD of
the spinning station 2. The arrangement may also be set up in such a
manner that the stopping devices 50 may be operated by the operating
personnel in that a button is pushed, in which case, it is best to mount
the push buttons or switches in the proximity of the pertaining drafting
unit 3.
The feeding rollers 8 and 9 are individual rollers 26 which are each
provided with side rims 25 and are non-rotatably mounted on a drive shaft
27 which extends through in the longitudinal direction of the machine and
is driven in a gearhead of the spinning machine 1.
In the embodiment according to FIGS. 3 and 4, the same reference numbers
were used for comparable components. In the following, these components
will therefore not be described again.
In the embodiment according to FIG. 3, instead of the feeding roller 8 of
FIG. 1, a tube 29 is provided above the can 5 which is provided with side
rims 28 and can stand or rotate but is not drivable. The sliver 6 is
therefore transported essentially by the feeding roller pair 7 of the
drafting unit 3.
The sliver 6 travels through a false-twisting element 30 which has a
bell-mouth-type inlet 31 and a bell-mouth-type outlet 32. By means of this
arrangement, an additional deflecting roller is avoided above the aisle 4
because the false-twisting element 30 also takes over the function of the
deflecting guide. At the end of the false-twisting course directly in
front of the feeding roller pair 7, another false-twisting element 33 of
the same type is situated. In addition to the saving of the upper
deflecting guide, the arrangement according to FIG. 3 has the additional
advantage that the sliver 6 is protected by a protective twist virtually
along the whole transport path between the tube 29 and the false-twisting
element 33. The false-twisting element 33 connected in front of the
drafting unit 3 has the bell-mouth shape only on its outlet 34 because a
slight deflection of the sliver 6 exists only in the direction of the
drafting unit 3.
Both false-twisting elements 30 and 33 are each disposed in a holder 35
which, in turn, is fastened to a longitudinal crosshead 36. The
longitudinal crossheads 36 are supported on the floor 12 corresponding to
the machine sections. In this case, it may be provided to design the
longitudinal crossheads in a vertically adjustable manner, as illustrated
in FIG. 4.
According to FIG. 4, a sliding muff 37 is fastened to the longitudinal
crosshead 36 and can be moved along a supporting rod 38. There is a chain
pulling device 39 which is guided around a deflecting pulley 40 and on
which the individual sliding muffs 37 are suspended. Thus, the possibility
exists to move the longitudinal crosshead 36 from a central point or in
sections upward or downward as required. This may be expedient, for
example, when a sliver 6 must be threaded through the false twisting
element 30. In this case, the longitudinal crosshead 36 is moved so far
downward that it is easy for the operating personnel to carry out the
threading operation.
The false twisting elements 30 and 33 are essentially constructed again as
tubes which can be driven on their exterior surface by a tangential belt
41.
As an alternative for the driving of the false twisting elements 30 and 33,
very simple miniature motors can be used and nowadays can be manufactured
at low cost. The precise rotational speed of the false-twisting elements
30 and 33 is not important because it is a temporary protective twist
which with respect to the spinning technology is not significant.
When the spinning machine 1 is started, it is advantageous to briefly
manually twist together the slivers 6 before they are pulled through the
false-twisting elements 30 and 33, as generally customary nowadays on the
flyer.
With a view to a uniform moving-out of all cans 5 of a spinning machine 1,
it is advantageous in the case of a yarn breakage to let the respective
sliver 6 continue to travel into the drafting unit 3 even if it is not
spun. It may then temporarily travel into a suction tube which is not
shown and is assigned to the drafting unit 3, as is frequently customary
in the case of ring spinning machines.
In the case of a corresponding design, it may be assumed that the
false-twisting element 30 to a certain degree has an effect that extends
into the can 5. Although the tube 29 is a twisting brake, it is no
twisting stop. The short area between the can 5 and the tube 29 will then
be slightly less twisted than the strand section 18 of the sliver 6.
With respect to faulty drafts, the strand section 18 is most dangerous. The
rotational speed of the false-twisting element 30 must therefore be
adjusted such that the sliver 6 receives a sufficient number of twists per
meter, for example, 50 twists or slightly less. This depends on the
strength of the respective sliver 6. The second vertical strand section 19
is slightly less dangerous but advantageously should receive the same
number of rotations as the first strand section 18. After leaving the
false-twisting element 33, the sliver 6 will be untwisted again so that it
can easily be drafted.
This false twist shortens the sliver 6. This is not very important in the
case of the variant according to FIG. 3 because the transport of the
sliver 6 is essentially commanded by the pair of feeding rollers 7 of the
drafting unit 3. However, in the case of the variant according to FIG. 1,
the pair of feeding rollers 7 must be coordinated with the feeding rollers
8 and 9. It is therefore important to let the drafting unit 3 run by an
amount of approximately 5 percent faster than the feeding roller 9
because, after the false twist opens up behind the false-twisting element
17, a loop would form after a short time.
Although the invention has been described and illustrated in detail, it is
to be clearly understood that the same is by way of illustration and
example, and is not to be taken by way of limitation. The spirit and scope
of the present invention are to be limited only by the terms of the
appended claims.
Top